An eating disorder is an illness that causes serious disturbances to your everyday diet, such as eating extremely small amounts of food or severely overeating. A person with an eating disorder may have started out just eating smaller or larger amounts of food, but at some point, the urge to eat less or more spiraled out of control. Severe distress or concern about body weight or shape may also signal an eating disorder. Common eating disorders include anorexia nervosa, bulimia nervosa, and binge-eating disorder.

Broad range of Information on types of eating disorders including statistics, diversity issues

Anorexia nervosa

"Anorexia nervosa, also called anorexia, is a potentially life-threatening eating disorder that is characterized by self-starvation and excessive weight loss. The disorder is diagnosed when a person weighs at least 15% less than his or her normal/ideal body weight. Extreme weight loss in people with anorexia nervosa can lead to dangerous health problems and even death.

The term anorexia literally means 'loss of appetite.' However, this definition is misleading as people with anorexia nervosa are often hungry but refuse food anyway. People with anorexia nervosa have intense fears of becoming fat and see themselves as fat even when they are very slender. These individuals may try to correct this perceived 'flaw' by strictly limiting food intake and exercising excessively in order to lose weight."

From "Helpguide.org", also discusses treatment, helping an acquaintance

Bulimia nervosa

Bulimia nervosa, commonly called bulimia, is a serious, potentially life-threatening eating disorder. People with bulimia may secretly binge — eating large amounts of food — and then purge, trying to get rid of the extra calories in an unhealthy way. Someone with bulimia may force vomiting or do excessive exercise. Sometimes people purge after eating only a small snack or a normal-size meal.

Binge Eating

Binge eating disorder was officially designated as a formal diagnosis in the 5th edition of the Diagnositic and Statistical Manual published by the American Psychiatric Association in 2013. In the previous edition of the manual, (DSM-IV), the diagnosis was listed in Eating Disorders Not Otherwise Specified (EDNOS) indicating that additional research was necessary... Binge eating disorder is characterized by recurring episodes of binge eating, feeling out of control while binging, and feeling guilt and shame afterward.

Men and Eating Disorders

Statistics indicate that women are far more likely than men to develop and be diagnosed with eating disorders, but that does not mean that all those with eating disorders are women, or that eating disorders are "women's" troubles.

"The only organization in the United States exclusively dedicated to representing and providing support to males with eating disorders... information and resources about and support to this underrepresented population and their families."